Download EGR Backpressure Transducer (EGR-BPT) & EGR Canister Backpressure Transducer (EGRC-BPT) Valves Plug one port of EGR-BPT (EGRC-BPT) valve and apply vacuum to other port. See Fig. 9 . Vacuum should NOT hold. Apply light pressure to bottom port (DO NOT apply more pressure than is necessary to cause vacuum to hold). If vacuum does not hold with pressure applied, replace EGR-BPT (EGRC-BPT) valve.